IIALTEIUCERUS. 119 



the peculiar structure of its appendages, distinguish this genus 

 sufficiently from all the other related genera. 



Only European species of Hypopliyllus are as yet known. 



The name of the genus (from vno, under, and $\>MOV, the leaf) 

 has reference to the mode of life of the species, found in shady 

 places on bushes and herbs and running on both sides of the leaves. 



Gen. XL HALTERICERUS. 



This genus was established by Mr. Rondani, in the year 1844, 

 in the Xth volume of the Annali delle scienze Naturali di Bo- 

 logna, under the name of Ludomcius, which afterwards, in the 

 first volume of the Prodromus Dipterologise Italicse, he changed 

 into Haltericerus. His statements with regard to the characters 

 of the genus are not sufficient and not altogether correct. I am 

 able to complete and to correct them as follows, from two Span- 

 ish species of my .own collection, which, according to Mr. Hali- 

 day, are also found in Upper Italy. 



The face of the male very narrow, that of the female compara- 

 tively very broad ; in both sexes it does not quite reach the lower 

 margin of the eye. Palpi small. The first joint of the antenna; 

 of the male large and very much inflated, in the female much 

 smaller and less inflated, in both sexes however beset on the upper 

 side only with extremely short, rather imperceptible hairs. The 

 second joint of the antennae in both sexes very small, rather rudi- 

 mental, somewhat imbedded into the first joint and only distin- 

 guishable by the bristles with which it is fringed at its end. The 

 third joint of the antenna in the females of all species appears to 

 be rounded ; in the males it has. either a more elongated or almost 

 a conical form. The arista of the female is plain, dorsal, two- 

 jointed, its first joint short. The arista of the male is also two- 

 jointed ; its first joint is filiform and very much elongated, the ab- 

 breviated second joint forms a flat lamella ; the position of the 

 arista in the males with an oval third joint is distinctly subapical, 

 in the other species it is apical or appears to be so. The neura- 

 tion of the wings resembles that of the species of Systenus, the 

 last segment of the fourth longitudinal vein being gently, but still 

 sufficiently inflected forward to approach with its end closely to 

 that of the third longitudinal vein. Feet slender, with scarce 

 bristles ; the first joint of the hind tarsi without bristles and much 



